There is a need for long lengths of an insulated electrical conductor wire encased in metal tubing, for example, in well bores for providing electrical power and/or making various measurements from various types of instruments. In such cases, the electrical cable may be of a long length, for example only, as much as 15,000 feet long. The manufacture of such cable is both expensive and difficult.
The present invention is directed to a method and apparatus for manufacturing long lengths of cable in which an insulated conductor is inserted in a metal tubing. And while the present method and apparatus can be used for manufacturing such a cable in a horizontal position, it is particularly advantageous to manufacture such a cable in a vertical position whereby various types of forces can be utilized such as gravity forces, vacuum forces, and pressure forces, to control the insertion of an insulated conductor into the inside of an outer metal tubing. In addition, in the vertical manufacturing mode, the present method and apparatus can be advantageously utilized in a well bore such as an abandoned oil or gas well thereby reducing the expenses of the manufacturing facilities.